Posted: May 01, 2017 2:07 pm
zulumoose wrote:I am quite naive in these things, but isn't the defining point of the species barrier the inability to interbreed and have fertile offspring?
How is this determined from fossils alone, wouldn't aged fossils of modern dogs or even humans show enough variation such that they would be determined by the same limited means of investigation to be different species instead of races or breeds of the same species?
In the case of pet dogs, humans play a large role in their phenotypic evolution (through selective breeding), making it seem that they were separate species. Humans don't have anything like as much phenotypic variation as pet dogs (some height and skin colour variation, plus face shape details, etc.).